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I believe this study does not control for whether the fat is hydrogenated or not. So they are really measuring the effects of trans-fats, which are already known to be bad.

That is my general concern with almost all of the nutrition research on fats. They are not grouping the fats appropriately. If you group butter and hyrogenated vegetable oils together because they are both "saturated" fats and then do your analysis lumping them together then you can't distinguish whether the problems caused by saturated fats are due to the hydrogenization or due to the butter being saturated or both.

Saturated fat consumption is decreasing, while unsaturated fat consumption is increasing, but people continue getting less healthy. So it seems the premise that saturated fats are that bad needs to be questioned. Or at least we need to ask if it's really saturated fats like coconut oil and butter that are bad or something that happens to the fats like canola oil when it is hydrogenated.

Edit: also as anecdotal evidence, what is the one common feature of almost all food generally considered harmful? Lots of processed vegetable oils in it, often in conjunction with sugar. I have not seen a reasonable explanation of how this can be the case if poly-unsaturated fats are as healthy as they are claimed to be.




> Saturated fat consumption is decreasing, while unsaturated fat consumption is increasing

Do you have any source for this? The best I could find suggests that this is probably untrue: "An increase in saturated fat in 2008-12 is notable in several product categories, especially breakfast cereals and yogurt (approximately 15 percent) and frozen/refrigerated meals (6 percent)." [0]

I'd welcome any kind of nutritional study you can reference that shows the problems you're raising with PUFAs. Even if the above studies mentioned didn't control for hydrogenation, if PUFAs were bad for you, we would expect to see poor outcomes from those consuming them. It's weird that people in that category actually did best in the study.

> what is the one common feature of almost all food generally considered harmful?

It's far simpler than looking at added sugar content or amount/type of fat -- the commonality is simply, how processed is this. Any whole food you can consider healthy, but most harmful food is processed (and most processed food is harmful!)

[0] https://www.ers.usda.gov/webdocs/publications/85761/eib-183....


But Canola oil is higher in monounsaturated fats like Olive Oil: https://medlineplus.gov/ency/patientinstructions/000785.htm

Why is Canola oil bad if it has the same quantity of monounsaturated fats as Olive Oil?


Because it has substantially more poly-unsaturated fats. See this graphic for info: https://cdn.mos.cms.futurecdn.net/4DmwKT6rrQf2BMJQwvX2cX-650...

It's not really that saturated or mono-unsaturated fats are good for you, but that poly-unsaturated fats are bad for you. I realize this is contrary to what much of modern nutrition says, but the lipid science says the poly-unsaturated fats are worse because they react more with other molecules in your body.

Also, saturated fat consumption has been declining and unsaturated fat consumption increasing over the past decades while health keeps getting worse. To me, this suggests that something is wrong with our current nutritional understanding, and I believe the lipid science shows that the problem is the poly-unsaturated fats (as one part of it at least, it's obviously not monocausal).




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